【作者】 张平冬；

【导师】 康向阳；

【作者基本信息】 北京林业大学 ， 林木遗传育种， 2009， 博士

【摘要】 围绕提高林地木材产量、缩短采伐周期的超短轮伐纸浆林经营目标,以及低投入、高产出的企业经营原则,首次以三倍体毛白杨无性系B301、B302、B305、B306、B307、B330、B331等为材料,在山东兖州开展了三倍体毛白杨容器育苗、超短轮伐纸浆材无性系选配以及超短轮伐(3年)定向栽培配套技术研究,探索三倍体毛白杨超短轮伐纸浆林经营的可行性。主要研究结果如下:(1)研究出一套三倍体毛白杨硬枝扦插容器育苗技术。研究表明,三倍体毛白杨“炮捻”和“一条鞭”嫁接插穗,以及硬枝和嫩枝插穗采用容器育苗法育苗均可取得较高的成活率,但从简化育苗技术环节、降低育苗成本角度考虑,选择根萌硬枝插穗作为三倍体毛白杨容器育苗的繁殖材料,容器苗成本低于0.20元/株。插穗、扦插基质以及插穗处理方法等对三倍体毛白杨硬枝扦插容器育苗影响显著,其中以沙壤土为基质,插穗粗度大于1.0cm、长12-14cm,插穗浸水24h后速蘸50ppm NAA+100ppmVB1混合液处理,三倍体毛白杨硬枝扦插容器育苗效果最好,成活率大于75.0%。(2)明确了三倍体毛白杨容器育苗直接造林的立地类型和造林时间。不同立地类型、造林时间对容器苗林分生长量影响极显著。其中以沙壤土较适宜三倍体毛白杨容器苗栽培;而容器苗造林从3月底至6月初均可以进行,但以4月份最好;容器苗直接造林无缓苗问题,可以避开用工高峰期,延长造林时间,且可直接打孔造林,不需要挖坑,造林成本为83.3元/亩,比大苗造林节省造林费7.8元/亩,尤其适宜于高密度超短轮伐期纸浆林培育。(3)明确了三倍体毛白杨超短轮伐栽培的适宜定植密度。无性系对超短轮伐纸浆林的树高、冠幅、冠长、树冠直径、树冠体积以及自然整枝高度的影响极显著,对材积影响显著,对胸径以及单株鲜重影响不显著;造林密度对胸径、材积、单株鲜重、冠幅、树冠直径以及树冠体积均影响极显著,对冠长影响显著,对树高影响不显著。不同三倍体毛白杨无性系的胸径生长随造林密度的增大而减小,而单位面积的材积生长量则随着造林密度的增大而增大。确定9990株/ha是三倍体毛白杨超短轮伐纸浆林经营的适宜密度;在9990株/ha的密度下,以无性系B307、B331、B302的材积生长量最大。(4)证明三倍体毛白杨超短轮伐栽培的木材纤维和化学组成基本适宜制浆造纸。从三倍体毛白杨无性系木材纤维和化学组成测试分析结果看,无性系对超短轮伐纸浆材的纤维长度、纤维宽度、木素含量、综纤维素含量、α-纤维素含量以及基本密度的影响极显著,对戊聚糖含量影响显著,对苯醇抽提物含量影响不显著;而造林密度只对木材的基本密度有显著影响。3年轮伐时,三倍体毛白杨的纤维长0.71-0.92mm,纤维长宽在23.00-31.36μm,基本满足造纸对纤维的要求;三倍体毛白杨木材的基本密度0.247-0.282g/cm~3,平均苯醇抽提物含量3.68-4.39%,戊聚糖平均含量12.86-13.47%,木素含量18.16-19.77%,综纤维素含量74.91-77.61%,α-纤维素含量40.28-43.49%,与短轮伐期纸浆材相比,其木材的基本密度和纤维素较低,表明超短轮伐纸浆材的木浆得率相对较低;其中在9990株/ha的密度下,超短轮伐纸浆林以无性系B302、B331的材性表现最佳。(5)从已有三倍体毛白杨中筛选出更适宜超短轮伐栽培的品系,可满足造纸企业的原料供应和经济发展要求。利用树干材积、纤维长度、纤维长宽比、综纤维素含量以及木材基本密度等与制浆造纸密切相关的生长和材性指标综合评价表明,三倍体毛白杨B331、B302更适宜超短轮伐栽培。与6年短轮伐期(含苗期)经营相比,尽管三倍体毛白杨无性系B331、B302超短轮伐经营年均赢利只有32.5元/亩,比4m×1.5m密度短轮伐期栽培每年少收入70.9元/亩。但超短轮伐6年可栽植两轮,共生产木材11.0m~3/亩,比短轮伐期栽培每亩多生产3.9m~3木材。按木浆得率折算,超短轮伐经营可多生产木浆0.32t/亩,即可从制浆环节增加收益,这对于极度缺乏原料的造纸企业具有一定的应用潜力。更多还原

【Abstract】 Experiments on container seedling-raising and selection of clones were firstly conducted to determine feasibility for intensive short-rotation of Populus tomentosa with clones B301、B302、B305、B306、B307、B330 and B331 as material based on the objective of increasing timber yield and shortening rotation period.Research results as follows:（1） Technology on hardwood cuttings container seedling-raising of triploid hybrids of Populus tomentosa was achieved:research results indicated that survival rates of container seedlings could be obtained with cleft-grafting cuttings、budding cuttings、hardwood cuttings and softwood cuttings as material.Hardwood cuttings were the simplest method of propagation which was from root suckers,and cost of container seedling was less than 0.20yuan RMB per tree.Sources of cuttings、media and treatment of cuttings had significant effect on hardwood cuttings container seedling.Optimum combinatorial technology was to treat hardwood cuttings whose thickness was above 1.0cm,length was from 12 to 14cm with 50ppm NAA+100ppm VB₁ after dipped in water for 24 hours with sandy soil as medium.And high Survival rates of hardwood cuttings could be above 75.0%.（2） Method of forestation for container seedlings was brought forward.Site type and time of planting had significant effect on growth of stands of container seedling of triploid hybrids.Sandy soil is a kind of site type for planting container seedling of Populus tomentosa.Time of planting container seedlings was from end of March to beginning of June.Forestation of container seedlings had many advantages,such as without the stage of slowly growing,avoid sharp time of labor force,prolonging time of forestation and simple procedure of forestation,which was particularly suitable to culture intensive short-rotation pulpwood.（3） optimum spacing for intensive short-rotation of Populus tomentosa was determined.Triploid clones of Populus tomentosa had significant effect on tree height、size of tree crown、length of tree crown、diameter of tree crown、volume of tree crown and natural spurning,great effect on stem volume of stands、no effect diameter at breast height and fresh weight of single tree、Spacing had significant effect on diameter at breast height、stem volume of stands、fresh weight of single tree、size of tree crown、diameter of tree crown and volume of tree crown,great effect on length of tree crown,no effect on tree height.Diameter at breast height of clones increased with spacing decreasing,stem volume of stands increased with spacing increasing.Stands planted with 9990 trees/ha brought about the largest stem volume when final cut in 3 years.9990 trees/ha was the appropriate spacing of intensive short-rotation of Populus tomentosa.Clones B307s B331 and B302 planted with 9990 trees/ha brought about the largest stem volume.（4）Characteristics of fiber and chemical components of intensive short-rotation pulpwood of triploid hybrids of Populus tomentosa were proved to be suitable for pulping.Results indicated that triploid clones had significant effect on length of fiber、width of fiber、content of lignin、content of holocellulose、content of a-cellulose and basic density,great effect on content of pentosan,no effect on phenol-alcohol extraction.Spacing had only great effect on basic density.Features of 3-year-old triploid hybrids that Length of fiber from 0.71mm to 0.92mm and mean ratio to length and width from 23.00 to 31.36 was to meet need of pulp & paper industry.Wood properties which basic density from 0.247 g/cm³ to 0.282 g/cm³,mean phenol-alcohol extraction from 3.68%to 4.39%,mean content of pentosan from 12.86%to 13.47%,mean content of lignin from 18.16%to 19.77%,mean content of holocellulose from 74.91%to 77.61%and mean content ofα-cellulose from 40.28%to 43.49%was little worse than short rotation pulpwood（5 years）.So craft yield would be little lower because of lower basic density and lower content of cellulose.Experimental results showed that wood property of intensive short-rotation pulpwood of clone B302 and B331 planted with 9990 trees/ha was the best.（5）Clones of intensive short-rotation of Populus tomentosa was screened to meet supply of raw material and need of economic development.A synthetical evalutation was conducted to determine wood quality and growth of intensive short-rotation pulpwood with stem volumes length of fiber、ratio to length and width of fiber、content of holocellulose and basic density as index,and clones B302 and B331 were selected out for intensive short-rotation management.Annual profit of intensive short -rotation pulpwood of clones B302 and B331 was 32.5yuan/mu.RMB Compared with short-rotation pulpwood（6 years）,annual profit was less than 70.9 yuan/mu.RMB 11.0m³/mu would be obtained for intensive short-rotation pulpwood.more than 3.9m³ stem volume or 0.32t/mu craft yield per year for short rotation pulpwood（6 years） planted with 4m×1.5m spacing when final cut was carried out in 6years.So intensive short-rotation management was of great potential to pulp & paper industry which was short of raw material.更多还原